Research On Fourth Party Logistics Routing Problem With Collaboration Among Third Party Logistics Servers

With the continuous development of economy,people have higher requirements for the efficiency of logistics.As an integrator of the supply chain,fourth party logistics(4PL)servers make optimized solutions in order to reduce operating costs for customers and improve the operational efficiency of each part in the supply chain.Transportation is the most important part in the process of logistics.Proper logistics route planning and resource allocation has great influence on logistics'efficiency.Based on the shortest path problem theory,fourth party logistics routing problem(4PLRP)is committed to optimizing the transportation route and selecting third party logistics(3PL)servers in a reasonable way to achieve efficient logistics.In previous studies,the 3PL server whose capacity can meet the total freight of one certain logistics task will be chosen between connecting nodes.However,those 3PL servers whose capacity can not meet the requirements of customers but have low transportation cost will be excluded,which leads to insufficient use of logistics resources and low operation efficiency of logistics network.Aiming at above problems,in order to improve the utilization of logistics resources,especially 3PL servers' transportation resources,further reduce logistics costs,create a fairer competitive environment,and achieve win-win situation of the whole logistics system,the research on 4PLRP with collaboration among 3PL servers has important meaning.Therefore,this paper will combine the knowledge of operational research and discuss the collaboration mode of 3PL servers in the traditional 4PLRP to provide a theoretical basis for the development of the logistics industry.Based on the summary of related research in 4PLRP,and according to the different collaboration modes of 3PL servers,this paper studied the 4PLRP with collaboration of 3PL servers between connected nodes and 4PLRP with collaboration of 3PL servers among the whole network.The specific contents of this thesis are as follows:(1)In 4PLRP with collaboration of 3PL servers between connected nodes,in order to minimize the total logistics cost,an integer programming model was established under the circumstances of single task from single supplier to single demander and multiple tasks from multiple suppliers to multiple demanders respectively.Then it was proved that the optimal value of 4PLRP with collaboration of 3PL servers between connected nodes is less than or equal to 4PLRP without collaboration among 3PL servers.After that,the paper illustrated the influence of the completion time,3PL management cost and node management cost on optimal solutions of the problem.According to the specific numerical examples,ILOG CPLEX was used to solve the problem.Through the analysis of parameters from the problem,it was found that 4PLRP with collaboration of 3PL servers between connected nodes can reduce the total logistics cost and improve the utilization of 3PL server' s resources.(2)In 4PLRP with collaboration of 3PL servers among the whole network,the logistics task was first discretized according to its freight,and it then could be seen as sub tasks whose freight is "1" unit.Therefore the optimization of a single path for logistics tasks was transformed into seeking an optimal network composed of optimal path of multiple logistics sub tasks.Then a 0-1 programming model was established under the circumstances of single task from single supplier to single demander.In the next,it was proved that the optimal value of 4PLRP with collaboration of 3PL servers among the whole network is less than or equal to 4PLRP with collaboration of 3PL servers between connected nodes.After that,the paper illustrated the influence of 3PL management cost and node management cost on optimal solutions of the problem.According to the specific numerical examples,ILOG CPLEX was used to solve the problem.Through the analysis of parameters from the problem,it was found that 4PLRP with collaboration of 3PL servers among the whole network can further reduce logistics costs,and expand the participation of the 3PL servers,which is superior to the mode just considering collaboration of 3PL servers between connected nodes.